One of the first questions a professional in the diamond trade may ask when looking at OpenFacet’s fancy-shape dashboard is: Why is there a ratio slider, but no total depth % slider? Some may also ask why there is not yet a fluorescence toggle. Fluorescence may be incorporated in the future, but for now, we would like to explain why total depth % was intentionally left out of the current dashboard.

When we began studying ratios and collecting data from online wholesale platforms, our goal was to gather as much reliable data as possible without weakening the integrity of the study. To do that, we set several strict rules designed to protect the calculations from false conclusions.

First, each shape had to be studied on one maker platform only. We did not combine data from multiple producers. The reason is simple: different producers serve different clients, target different markets, and may price their goods according to different business models. Mixing those datasets would have created noise and reduced reliability.

Second, for each shape we kept polish and symmetry at Very Good and above, and fluorescence at None. This was done to reduce unnecessary variables and keep the comparison focused.

Third, we avoided using oversized stone data that could distort the calculations.

Fourth, each shape had to be measured through at least three comparison pairs across the 0.50 ct, 1 ct, and 2 ct ranges, and then compared against rounds on the same platform.

With these controls in place, the work was extremely difficult. As everyone in the trade knows, once you move into fancy shapes and then try to maintain these conditions across those size points, the available data becomes very thin, especially in the 2-carat range.

Adding another layer, such as total depth %, whether as a broad range like 60%–67% or according to an “ideal depth” per shape, would have narrowed the dataset even further and made it impossible at a given time. It would have made the result less reliable, because the sample size would become too small.

There is also a deeper reason. Total depth % cannot be imposed in the same way across a wide range of fancy shapes. The longer the shape, the less total depth % alone explains its visual outcome. In other words, depth matters, but it does not behave as a universal benchmark variable in the same way ratio does.

Since the ratio study was conducted using data from prominent and well-established trade players, the stones examined were already generally within commercially accepted standards for each shape. That is important. When an attribute is not separately isolated in a study like this, but the goods are already filtered by market reality, it usually means that the attribute is already embedded in the market behavior of the variable being studied.

A useful analogy is race cars.

If we were studying race cars, power and torque would be like a diamond’s color, clarity, and weight. The weight of the car would be like the ratio of a fancy shape. Its aerodynamic coefficient would be like total depth %.

Aerodynamics clearly matter. They influence launch, balance, grip, and overall performance. But top race-car manufacturers already strive to optimize aerodynamics. So if we compare race cars by power, torque, and weight alone, we can still reach a very true understanding of their performance, even if we do not separately isolate aerodynamic efficiency in every comparison. In the same way, total depth % still matters in fancy shapes, but when studying real market pricing, much of its influence is already absorbed into the commercial reality of the stones offered.

This is why ratio proved to be the stronger benchmark variable for the OpenFacet dashboard. It gives us a measurable, market-reflective, and sufficiently broad basis for analysis without collapsing the dataset into something too thin to trust.

Lastly, OpenFacet is fully aware that, in the diamond trade, a benchmark price list is still followed by negotiation. We do not intend, nor aspire, to “price diamonds” in the absolute sense. Our goal is to create a true benchmark that reflects real market data with as little human intervention as possible — something the diamond industry has been missing for a very long time.